Vibration structure of electrical toothbrush

Abstract

A vibration structure of electrical toothbrush includes an eccentric rod. Two ends of the eccentric rod are respectively formed with a transmission section and a weight section. The transmission section is drivable by a driving force to rotate so as to drive the weight section to eccentrically vibrate. The weight section has an opening and a receiving space inward recessed from the opening. A cover member is correspondingly mated with the opening to cover the same. A weight block is disposed in the receiving space to partially or totally increase the weight of the weight section, whereby due to the increased weight, the weight section is unbalanced in weight to deflect from a central axis of the eccentric rod.

What is claimed is: 
     
       1. A vibration structure of electrical toothbrush comprising:
 an eccentric rod, two ends of the eccentric rod being respectively formed with a transmission section and a weight section, the transmission section being drivable by a driving force to rotate so as to drive the weight section to eccentrically vibrate, the weight section being a hollow cylindrical body having an opening formed at a periphery of the hollow cylindrical body, the opening partially extending along a transversal length of the weight section and a receiving space inward recessed from the opening, a weight block being disposed in the receiving space and having a semicircular cross-section, a polygonal cross-section, or any geometric cross-section to partially or totally increase the weight of the weight section, whereby the weight section is unbalanced in weight to deflect from a central axis of the eccentric rod; and 
 a cover member correspondingly mated with the opening to cover the same. 
 
     
     
       2. The vibration structure of electrical toothbrush as claimed in  claim 1 , wherein the cover member is correspondingly mated with weight section to close an outer surface of the weight section. 
     
     
       3. The vibration structure of electrical toothbrush as claimed in  claim 1 , wherein the receiving space has a circular cross section, a polygonal cross section or any geometrical cross section corresponding to the cover member. 
     
     
       4. The vibration structure of electrical toothbrush as claimed in  claim 1 , wherein the weight block is made of metal or nonmetal material. 
     
     
       5. The vibration structure of electrical toothbrush as claimed in  claim 1 , wherein the weight block and the receiving space are integrally formed or are securely connected with each other by means of insert injection molding, adhesion, engagement, press fit, welding or screwing. 
     
     
       6. The vibration structure of electrical toothbrush as claimed in  claim 1 , wherein the weight section is formed with two perforations corresponding to the opening, the two perforations radially passing through the outer surface of the weight section, the outer surface of the weight section being recessed to form two hooked holes corresponding to the perforations, the cover member being formed with two hook legs corresponding to the opening, a free end of each hook leg having a hooking section, the hook legs being respectively passed through the perforations and the hooking sections being respectively hooked in the hooked holes. 
     
     
       7. The vibration structure of electrical toothbrush as claimed in  claim 1 , further comprising a drive source, a vibration stem and a cleaning fitting head, the drive source serving to output the driving power, the drive source being correspondingly connected with one end of the transmission section distal from the weight section to output the driving power to the eccentric rod, the vibration stem having a first closed end and a first open end, the first closed end and the first open end together defining a first space, a first assembling section protruding from the first closed end to the first space, one end section of the weight section distal from the transmission section having a second assembling section, the eccentric rod being placed into the first space from the first open end, the first assembling section being correspondingly connected with the second assembling section, the cleaning fitting head having a second closed end and a second open end, the second closed end and the second open end together defining a second space, a brush section being disposed on outer side of the second closed end, the cleaning fitting head being fitted around the vibration stem via the second space. 
     
     
       8. The vibration structure of electrical toothbrush as claimed in  claim 1 , wherein the eccentric rod and the cover member are made of thermoplastic material.